CNS Metastases in Breast Cancer

Abstract
As systemic therapy of metastatic breast cancer improves, CNS involvement is becoming a more widespread problem. This article summarizes the current knowledge regarding the incidence, clinical presentation, diagnosis, prognosis, and treatment of CNS metastases in patients with breast cancer. When available, studies specific to breast cancer are presented; in studies in which many solid tumors were evaluated together, the proportion of patients with breast cancer is noted. On the basis of data from randomized trials and retrospective series, neurosurgery and stereotactic radiosurgery (SRS) may prolong survival in patients with single brain metastases. The treatment of multiple metastases remains controversial, as does the routine use of whole-brain radiotherapy (WBRT) after either surgery or SRS. Although it is widely assumed that chemotherapy is of limited benefit, data from case series and case reports suggest otherwise. WBRT, neurosurgery, SRS, and medical therapy each have a role in the treatment of CNS metastases; however, neurologic symptoms frequently are not fully reversible, even with appropriate therapy. Studies specifically targeted toward this group of patients are needed.